Today, the great peacekeeper is ill: to ask the question of the legitimacy of the United Nations to safeguard peace. The postwar context is different from that of the early 21st century but the International Institution has difficulty to follow.
« I call on all warring parties to lay down their weapons and observe a global ceasefire. To them, I say: stop the killings and the destruction and create space for lasting peace. »  These words are pronounced by UN Secretary-General Ban Ki-moon for the Day of Peace. The International Day of Peace was established in 1981. The first peace day was observed in September 1982 and in 2001, the General Assembly established 21 September as an annual day of non-violence and cease-fire: « all nations and people to honour a cessation of hostilities during the Day, and to otherwise commemorate the Day through education and public awareness on issues related to peace. » 
One question remains: how the United Nation manages to keep the peace?
This year the UN celebrates its 70 candles. The institution is created after the Second World War. Its main aim is to keep the Peace in the World. But it seems that the United Nations has some problems maintaining peace like its predecessor, The League of Nations. We note its inefficiency about the Syrian conflict and its inability to find a solution to the Israeli-Palestinian issues. Since 2005 the institution subcontracts mercenaries to help in its mission to maintain peace in conflict areas; however, the mercenaries activities are supervised by any international law. “There is more and more abuse committed with impunity by the employees of these companies” reports Le Monde. Then Security Council lacks democratic legitimacy, the veto power granted to only five of its members: Russia, United Kingdom, France, China and the United States. Its powers include the acceptance of new members to the United Nations and the approval of any changes to the United Nations Charter. Finally UN lack of money. The institutions would need $ 20 billion in 2015 for their humanitarian missions: just 7.15 billion were collected, report the Guardian. 
In 70 years the institutions of UN have never changed. However, the context of 1945 is not the context of 2015. Today, UN needs fundamental reform. Reforms that remove the prerogatives of the Security Council and guarantee the economics, means to realize its main objective: to keep the peace. By Giuseppe Orobello
 BAN-KI MOON, «Speech for the International Day of Peace. 21 September 2015», in un.org. URL: http://www.un.org/en/events/peaceday
 «International Day of Peace 21 September », in unhcr.org. URL: http://unhcr.org.au/unhcr/index.php?option=com_content&view=article&id=334&catid=49&Itemid=72
 “League of Nations”, in wikipedia.org. URL: https://en.wikipedia.org/wiki/League_of_Nations
 MAURISSE Marie, “Quand l’ONU, gage de paix dans le monde, recourt à des mercenaires”, in lemonde. fr. http://www.lemonde.fr/international/article/2015/06/04/quand-l-onu-gage-de-paix-dans-le-monde-recourt-a-des-mercenaires_4647309_3210.html
 We find the report about global humanitarian assistance for 2015 on http://www.globalhumanitarianassistance.org/wp-content/uploads/2015/06/GHA-Report-2015_-Interactive_Online.pdf